xref: /curl/docs/examples/smtp-expn.c (revision f540e43b)
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8  * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
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10  * This software is licensed as described in the file COPYING, which
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19  * KIND, either express or implied.
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21  * SPDX-License-Identifier: curl
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24 
25 /* <DESC>
26  * Expand an SMTP email mailing list
27  * </DESC>
28  */
29 
30 #include <stdio.h>
31 #include <string.h>
32 #include <curl/curl.h>
33 
34 /* This is a simple example showing how to expand an email mailing list.
35  *
36  * Notes:
37  *
38  * 1) This example requires libcurl 7.34.0 or above.
39  * 2) Not all email servers support this command.
40  */
41 
main(void)42 int main(void)
43 {
44   CURL *curl;
45   CURLcode res;
46   struct curl_slist *recipients = NULL;
47 
48   curl = curl_easy_init();
49   if(curl) {
50     /* This is the URL for your mailserver */
51     curl_easy_setopt(curl, CURLOPT_URL, "smtp://mail.example.com");
52 
53     /* Note that the CURLOPT_MAIL_RCPT takes a list, not a char array  */
54     recipients = curl_slist_append(recipients, "Friends");
55     curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);
56 
57     /* Set the EXPN command */
58     curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "EXPN");
59 
60     /* Perform the custom request */
61     res = curl_easy_perform(curl);
62 
63     /* Check for errors */
64     if(res != CURLE_OK)
65       fprintf(stderr, "curl_easy_perform() failed: %s\n",
66               curl_easy_strerror(res));
67 
68     /* Free the list of recipients */
69     curl_slist_free_all(recipients);
70 
71     /* curl does not send the QUIT command until you call cleanup, so you
72      * should be able to reuse this connection for additional requests. It may
73      * not be a good idea to keep the connection open for a long time though
74      * (more than a few minutes may result in the server timing out the
75      * connection) and you do want to clean up in the end.
76      */
77     curl_easy_cleanup(curl);
78   }
79 
80   return 0;
81 }
82